Wave upwelling effects in TLP and semisubmersible structures

Mutual hydrodynamic interaction effects between closely spaced large columns can cause substantial increases in local wave height and in other kinematic quantities. This phenomenon of upwelling is here analysed theoretically, by using a high order hybrid element technique. Results are presented as contour plots and isometrics of local free surface amplitudes in regular waves; linear transfer functions of wave amplitude at a point; mean square wave amplitudes in long crested random seas; and local components of horizontal velocity in regular waves. It is suggested that wave upwelling is an important phenomenon which should be considered in design.